How do i make max level higher on WoW 3.3.5a Pserver

Hello guys i have a question
How do i make the max level higher on WoW 3.3.5a Pserver( The old version of 335a)

Greetings Nervnico

Up to 255, look in the config file for the worldserver.

If you want to go beyond 255 you have to do some work, since maxLevel in most, if not all, instanced is saved as an unsigned 8bit integer, meaning it has an upper bound of 255.
If you where to change it to an unsigned 16bit integer (next bigger type) you could go to 32767 as max level.